9.16 Intrauterine Fetal Death And Stillbirth

Question 1

Define Stillbirth & Fetal death

Answer 1

Stillbirth - newborn at _> 28 weeks of gestation with no signs of life at birth (viable baby born dead)

Fetal death - intrauterine death at any time during pregnancy (antepartum or intrapartum)

Question 2

Maternal Risk factors for fetal demise and stillbirth

Answer 2

Sociodemographic
- black race
- significant life events
- extreme ages
- unmarried
- nulliparity/_>3
- enviromental stressors

Previous pregnancy
- previous still birth
- previous adverse pregnancy outcome

Comorbid medical disorders
- diabetes
- hypertensive disorders
- substance use
- antiphospholipid syndrome
- obesity
- SLE
- chronic kidney disorders

Uterine abnormalities
- uterine rupture
- congenital anomalies of uterus
- amniotic band syndrome

Question 3

Fetal risk factors for fetal demise and stillbirth

Answer 3

Multiple gestation
- Fetal mortality increases with increasing number of fetuses.
- 2.5-fold for twins
- 5-fold for triplets
- Increased in MCDA placentation

Male sex
- male:female = 6.23:5.74

Postterm pregnancy
- 2x ⬆️ _>42 weeks
- 4x ⬆️ >43 weeks
- 5-7x ⬆️> 44 weeks

Question 4

Aetiology of fetal death
Maternal
Obstetrics
Placental
Umbilical cord
Fetal

Answer 4

Maternal causes:
- Infections – chorioamnionitis/systemic

Obstetric causes:
- Prolonged labour
- Intrapartum asphyxia
- Uterine rupture
- Shoulder dystocia

Placental causes:
- Abruptio placentae
- Ruptured vasa praevia
- Fetal growth restriction – early vs late
- Placental insufficiency
- Confined placental mosaicism

Umbilical cord abnormalities:
- Cord entrapment/nuchal cord
- Umbilical cord knots
- Cord prolapse

Fetal causes:
- Congenital anomalies.
- Fetal growth restriction
- Genetic abnormalities – T21, T18, T13, 45X
- Hydrops fetalis – immune vs non-immune
- Fetal arrhythmia

Question 5

Systemic vs intra-uterine maternal infection

Answer 5

Systemic
- Chorioamnionitis
- secondary to ascending infection from the vagina and cervix – usually polymicrobial from vaginal and enteric flora.

Maternal systemic disease
- pneumonia
- COVID-19
- pyelonephritis
- severe sepsis
- malaria
- Zika
- Syphilis
- Toxoplasmosis
- CMV

Question 6

Examples of congenital abnormalities

Answer 6

caused by genetic abnormality or environmental exposure

• abdominal wall defects
• neural tube defects
• lethal skeletal dysplasia
• amniotic band syndrome

Question 7

Fetal growth restriction
Define
Causes
Classification

Answer 7

Fetus does not meet its genetic growth potential

Def - EFW {estimated fetal weight} below the 3rd percentile, with or without Doppler abnormalities.

Causes
- Interplay between maternal, placental and fetal factors.

Classification
- <32/40 = Early FGR
- ≥32/40 = Late FGR
Or
- Symmetrical IUGR
- Asymmetrical IUGR

2nd most common aetiology of stillbirth

Question 8

Hydorps Fetalis

Answer 8

Presence of at least 2 abnormal fluid collections in the fetus, including fluid in the serous cavities and generalised skin oedema.

Examples:
- pleural effusion
- pericardial effusion
- ascites
- oedema

• Immune vs non-immune

Question 9

Abruptio Placentae

Answer 9

Def - premature separation of placenta from the decidua after 20 weeks of gestation
- risk of stillbirth is highest when more than 50% of the placental surface becomes separated / abruption affects central portion
- vaginal bleeding not always accurate predictor of maternal haemorrhage

Signs
- abdominal pain
- contractions
- dark red vaginal bleeding
- rigid & tender uterus

Question 10

Ruptured vasa praevia

Answer 10

• Fetal blood vessels are present in the membranes covering the internal os.
• Diagnosed made by visualising fetal vessels overlying the internal os, via color doppler.
• VE – pulsating fetal vessels.

!!!! Avoid vaginal examinations
- Risk of rupture of fetal vessels and subsequent fetal haemorrhage and exsanguination within minutes, with spontaneous or iatrogenic rupture of membranes

Question 11

Name umbilical cord abnormalities

Answer 11

• nuchal cord
• knot
• torsion
• stricture
• prolapse (EMERGENCY)

Question 12

Perinatal asphyxia
Define
Causes

Answer 12

• Lack of oxygen to organ systems due to a hypoxic or ischaemic insult that occurs in close proximity to labour and delivery.
• May lead to multi-organ failure – brain is the major organ involved.
• Often a result of poor labour management.

Causes:
- maternal (impaired oxygenation; inadequate perfusion of maternal placenta)
- placental (abruptio placenta; tight nuchal cord; cord prolapse)
- fetal (impaired fetal oxygenation/perfusion)